title: Comparison of the Easyshade Compact and Advance in vitro and in vivo.
abstract: OBJECTIVE
  The objective of this study was to evaluate the repeatability, inter-examiner and inter-device reliability, and accuracy of the new VITA Easyshade Advance (ES-A) spectrophotometer in comparison with the Easyshade Compact (ES-C).
  
  
  METHODS
  For the in vitro study, six porcelain disks of random shade mixtures were fabricated from VITA ceramic powders. To analyze the repeatability of the ES-C and ES-A, readings were obtained by one examiner for one porcelain disk and one shade tab (VITA 3D-Master). Measurements were repeated by two examiners to evaluate inter-examiner reliability. To assess accuracy, porcelain disks and shade tabs were measured with the ES-C and ES-A and by means of a spectroradiometer (SR). ∆E values between the shade tabs and disks were calculated. Differences between devices were evaluated by use of univariate analysis. Reliability and accuracy of both devices were also tested in a clinical setting. The intra-class correlation coefficient (ICC) was calculated for all assessments of reliability.
  
  
  RESULTS
  Good agreement was observed for replicate measurements (ICC > 0.9), for inter-examiner reliability of the ES-A and ES-C (ICC > 0.9), and for inter-device agreement (ICC > 0.9). Univariate analysis revealed that ∆E values for the spectrophotometers were consistent (p = 0.783); spectroradiometrically measured ∆E was comparable, but the mean value was smaller than that for the spectrophotometers (p = 0.004). Clinical inter-device agreement was acceptable to high (ICC > 0.777). The accuracy of the ES-A was higher than that of the ES-C (p = 0.001).
  
  
  CONCLUSIONS
  Within the limitations of the experiment, the spectrophotometers tested enabled reliable and accurate measurement. In the clinical setting, however, the ES-A seems more accurate.
  
  
  CONCLUSIONS
  ES-C and ES-A can be valuable tools for the determination of tooth colors. Because of their good reliability, they should especially be used for the assessment of tooth color changes over time.
authors.affiliation: Department of Prosthodontics, Dental School, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany, andreas.zenthoefer@med.uni-heidelberg.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Zenthöfer
authors.forename: Tomas
authors.initials: T
authors.lastname: Cabrera
authors.forename: Nicoleta
authors.initials: N
authors.lastname: Corcodel
authors.forename: Peter
authors.initials: P
authors.lastname: Rammelsberg
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Hassel
mesh_terms: D003116:Color; D066298:In Vitro Techniques; D015203:Reproducibility of Results; D013053:Spectrophotometry / Q000592:standards; D014070:Tooth